Antenna module and method for inspecting antenna module

ABSTRACT

An antenna module includes a base member, an antenna that includes a radiating element disposed in or on the base member, first and second feed lines each of which is connected to the radiating element, and a control circuit that is connected to the radiating element via the first feed line and the second feed line. The control circuit includes a signal processing circuit that is connected to the antenna via the first feed line and the second feed line and an antenna inspection circuit that checks an electrical conductivity of an electrical conduction path connecting the first feed line, the radiating element, and the second feed line to one another.

CROSS REFERENCE TO RELATED APPLICATION

This is a continuation of U.S. patent application Ser. No. 16/837,375filed on Apr. 1, 2020, which is a continuation of InternationalApplication No. PCT/JP2018/028714 filed on Jul. 31, 2018 which claimspriority from Japanese Patent Application No. 2017-193499 filed on Oct.3, 2017. The contents of these applications are incorporated herein byreference in their entireties.

BACKGROUND Technical Field

The present disclosure relates to an antenna module and a method ofinspecting an antenna module.

Patent Document 1 describes a communication device that includes anantenna member and a method for checking a communication device. Thecommunication device described in Patent Document 1 includes an antennaconductor and an antenna terminal connected to the antenna conductor.The antenna conductor is covered with a coating layer. The antennaterminal is a terminal that is not covered with the coating layer andthat is used for an electrical conductivity check. The communicationdevice described in Patent Document 1 performs an electricalconductivity check as an inspection of the communication device bybringing a probe into contact with the antenna terminal and a groundterminal.

-   Patent Document 1: Japanese Unexamined Patent Application    Publication No. 2014-11746

BRIEF SUMMARY

In the method for checking electrical conductivity that is described inPatent Document 1, it is necessary to bring a probe into contact witheach antenna terminal, and for example, in the case of inspecting alarge number of communication devices or in the case where acommunication device includes a large number of antenna conductors, itmay not be easy to perform electrical conductivity checks.

The present disclosure provides an antenna module on which an electricalconductivity check can be easily performed and a method for inspectingan antenna module.

An antenna module according to an aspect of the present disclosureincludes a base member, an antenna that includes a radiating elementdisposed in or on the base member, a first feed line and a second feedline that are connected to the radiating element, and a control circuitthat is connected to the radiating element via the first feed line andthe second feed line. The control circuit includes a signal processingcircuit that is connected to the antenna via the first feed line or thesecond feed line and an antenna inspection circuit that checks anelectrical conductivity of an electrical conduction path connecting thefirst feed line, the radiating element, and the second feed line to oneanother.

According to an antenna module and a method for inspecting an antennamodule of the present disclosure, an electrical conductivity check canbe easily performed.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

FIG. 1 is a plan view of an antenna module according to a firstembodiment.

FIG. 2 is a sectional view taken along line II-II′ of FIG. 1 .

FIG. 3 is a sectional view taken along line III-III′ of FIG. 2 .

FIG. 4 is a block diagram illustrating a configuration example of theantenna module according to the first embodiment.

FIG. 5 is a graph schematically illustrating a relationship between anoutput signal and an electrical conductive condition of an antenna.

FIG. 6 is a flowchart illustrating a method for checking the electricalconductivity of the antenna module according to the first embodiment.

FIG. 7 is a flowchart illustrating another example of the method forchecking the electrical conductivity of the antenna module according tothe first embodiment.

FIG. 8 is a block diagram illustrating a configuration example of anantenna module according to a modification of the first embodiment.

FIG. 9 is a plan view illustrating radiating elements of an antennamodule according to a second embodiment.

FIG. 10 is a block diagram illustrating a configuration example of theantenna module according to the second embodiment.

FIG. 11 is a flowchart illustrating a method for checking the electricalconductivity of the antenna module according to the second embodiment.

FIG. 12 is a sectional view illustrating an antenna module according toa third embodiment.

FIG. 13 is a sectional view illustrating an antenna module according toa first modification of the third embodiment.

FIG. 14 is a sectional view illustrating an antenna module according toa second modification of the third embodiment.

FIG. 15 is a sectional view illustrating an antenna module according toa third modification of the third embodiment.

FIG. 16 is a sectional view illustrating an antenna module according toa fourth modification of the third embodiment.

FIG. 17 is a block diagram illustrating a configuration example of anantenna module according to a fourth embodiment.

FIG. 18 is a block diagram illustrating a configuration example of anantenna module according to a first modification of the fourthembodiment.

FIG. 19 is a block diagram illustrating a configuration example of anantenna module according to a second modification of the fourthembodiment.

FIG. 20 is a block diagram illustrating a configuration example of anantenna module according to a third modification of the fourthembodiment.

FIG. 21 is a sectional view illustrating an antenna module according toa fifth embodiment.

DETAILED DESCRIPTION

Embodiments of the present disclosure will be described in detail withreference to the drawings. The present disclosure is not limited to thecontents that are described in the following embodiments. Componentsthat will be described below include components that can be easilyconsidered by those skilled in the art, components that aresubstantially the same with each other, and components that areso-called equivalents. In addition, the components that will bedescribed below can be suitably combined. Furthermore, there is a casewhere some of the components are not used.

First Embodiment

FIG. 1 is a plan view of an antenna module according to a firstembodiment. FIG. 2 is a sectional view taken along line II-II′ of FIG. 1. FIG. 3 is a sectional view taken along line III-III′ of FIG. 2 . Asillustrated in FIG. 1 , an antenna module 1 of the present embodimentincludes a base member 10, a first antenna 20-1, a second antenna 20-2,a third antenna 20-3, a fourth antenna 20-4, a fifth antenna 20-5, and asixth antenna 20-6. Note that, in the following description, when it isnot necessary to distinguish the first antenna 20-1, the second antenna20-2, the third antenna 20-3, the fourth antenna 20-4, the fifth antenna20-5, and the sixth antenna 20-6, they will be referred to as theantennas 20. Each of the antennas 20 includes a radiating element 21(not illustrated) and a parasitic element 22.

In the following description, one direction in a plane parallel to afirst surface 10 a of the base member 10 will be referred to as an Xdirection. A direction that is perpendicular to the X direction in theplane parallel to the first surface 10 a will be referred to as a Ydirection. A direction that is perpendicular to the X direction and theY direction will be referred to as a Z direction. Note that therelationship between these directions is not limited to the above, andthe Y direction may intersect the X direction at an angle other than 90degrees. The Z direction may intersect the X direction and the Ydirection, each at an angle other than 90 degrees.

As illustrated in FIG. 1 , the plurality of antennas 20 are arranged ina matrix. In other words, some of the antennas 20 are arranged in the Xdirection, and some of the antennas 20 are arranged in the Y direction.The antenna module 1 is an array antenna that includes the plurality ofantennas 20.

As illustrated in FIG. 2 , the antenna module 1 further includes acontrol circuit 30, first feed lines 33, and second feed lines 34. Thebase member 10 has the first surface 10 a and a second surface 10 b thatis opposite to the first surface 10 a. For example, the base member 10is formed of a low-temperature co-fired ceramic multilayer substrate (anLTCC multilayer substrate). The base member 10 includes a plurality ofinsulating layers laminated together in the Z direction. Each of theinsulating layers is made of a ceramic material that can be fired at alow temperature of 1,000° C. or lower and is formed into a thin layer.Note that the base member 10 is not limited to this and may be amultilayer resin substrate that is formed by laminating a plurality ofresin layers each of which is made of a resin, such as an epoxy resin ora polyimide resin. In addition, the base 10 may be formed by using aliquid crystal polymer (LCP) or a fluorine-based resin that has a lowerdielectric constant. Alternatively, the base member 10 may be a ceramicmultilayer substrate. The base member 10 may be a flexible wiring boardhaving flexibility or may be a rigid printed board havingthermoplasticity.

The antennas 20 are, for example, patch antennas that are used forhigh-frequency signals within a bandwidth of 60 GHz, which is used bywireless gigabit (WiGig). Each of the antennas 20 includes the radiatingelement 21 and the parasitic element 22. Each of the radiating elements21 is disposed in or on an inner layer of the base member 10. Theparasitic elements 22 are disposed on the first surface 10 a of the basemember 10 so as to face the corresponding radiating elements 21. Each ofthe parasitic elements 22 is disposed so as to be superposed with thecorresponding radiating element 21 with at least one of the insulatinglayers of the base member 10 interposed therebetween. In other words,the parasitic elements 22 are insulated from the radiating elements 21.The radiating elements 21 and the parasitic elements 22 are each made ofa metallic material having electrical conductivity, examples of themetallic material including copper, silver, gold, and alloy materialscontaining these metals.

As illustrated in FIG. 1 , some of the parasitic elements 22 arearranged in the X direction, and some of the parasitic elements 22 arearranged in the Y direction. Similarly, as illustrated in FIG. 3 , someof the radiating elements 21 are arranged in the X direction, and someof the radiating elements 21 are arranged in the Y direction. Asillustrated in FIG. 1 and FIG. 3 , when viewed in plan view, theradiating elements 21 and the parasitic elements 22 have the same shape,which is a quadrangular shape. Note that the radiating elements 21 andthe parasitic elements 22 are not limited to having a quadrangular shapeand may each have another shape such as a circular shape or a polygonalshape. In addition, the shapes of the radiating elements 21 and theshapes the parasitic elements 22 may be different from each other.

As illustrated in FIG. 2 , a first end of each of the first feed lines33 and a first end of each of the second feed lines 34 are connected toone of the radiating elements 21. Second ends of the first feed lines 33and second ends of the second feed lines 34 are connected to the controlcircuit 30 via connection terminals 31.

The first feed lines 33 and the second feed lines 34 include vias 27,pads 28, and wiring lines 29. The vias 27 are formed as columnarconductors that extend through at least one insulating layer of the basemember 10 in the Z direction. More specifically, the vias 27 are formedby providing a metallic material having electrical conductivity inthrough holes that extend through the insulating layers. Each of thepads 28 is disposed between the insulating layers so as to connect thevias 27 that are adjacent to each other in the Z direction to each otheror so as to connect one of the vias 27 and one of the wiring lines 29 toeach other. Each of the wiring lines 29 is disposed in or on an innerlayer of the base member 10 so as to connect some of the vias 27 thatare located at different positions when viewed in plan view. Similar tothe radiating elements 21, the vias 27, the pads 28, and the wiringlines 29 are made of a metallic material having electrical conductivity.

The first feed lines 33 are connected to the corresponding radiatingelements 21 at first ports 23. The second feed lines 34 are connected tothe corresponding radiating elements 21 at second ports 24. Asillustrated in FIG. 3 , each of the first ports 23 is provided at aposition that is displaced from the center 21 c of one of the antennas20 in the Y direction. Here, each of the radiating elements 21 has twosides 21 s 1 and 21 s 2 that oppose each other in the X direction andtwo sides 21 s 3 and 21 s 4 that are located between the side 21 s 1 andthe side 21 s 2. The center 21 c coincides with an intersection point ofan imaginary line connecting the midpoint of the side 21 s 1 and themidpoint of the side 21 s 2 and an imaginary line connecting themidpoint of the side 21 s 3 and the midpoint of the side 21 s 4. Each ofthe first ports 23 is located in the vicinity of the side 21 s 4 of oneof the radiating elements 21, the side 21 s 4 extending in the Xdirection. Each of the second ports 24 is located at a position that isdisplaced from the center 21 c of one of the antennas 20 in the Xdirection. The second ports 24 is located in the vicinity of the side 21s 2 of one of the radiating elements 21, the side 21 s 2 extending inthe Y direction.

As illustrated in FIG. 2 , the control circuit 30 is mounted on thesecond surface 10 b of the base member 10 via the connection terminals31. The connection terminals 31 are, for example, solder ball bumps. Thecontrol circuit 30 is sealed with a sealing resin 11. The controlcircuit 30 is a circuit that controls transmission and reception ofsignals via the antennas 20 and that controls electrical conductivitychecks between the first feed lines 33, the radiating elements 21 of theantennas 20, and the second feed lines 34. The control circuit 30 is,for example, a radio frequency integrated circuit (RFIC).

With such a configuration, in the antenna module 1, the control circuit30 and each of the antennas 20 are electrically connected to each other.More specifically, in the antenna module 1, the first feed lines 33, theradiating elements 21 of the antennas 20, and the second feed lines 34are connected to the control circuit 30 via the connection terminals 31.As a result, in the antenna module 1, electrical conduction paths thatconnect the first feed lines 33, the radiating elements 21 of theantennas 20, and the second feed lines 34 to one another each form aclosed loop circuit.

When a signal processing circuit 50 (see FIG. 4 ) of the control circuit30 supplies a high-frequency signal to the first ports 23, a currentflows through the radiating element 21 in the Y direction. This currentflowing in the Y direction causes polarized waves that are parallel tothe Y direction to be radiated. When the signal processing circuit 50(see FIG. 4 ) of the control circuit 30 supplies a high-frequency signalto the second ports 24, a current flows through the radiating element 21in the X direction. This current flowing in the X direction causespolarized waves that are parallel to the X direction to be radiated. Asa result, the polarized waves of the antennas 20 can be switched bysupplying the high-frequency signal to the first ports 23 or the secondports 24.

When the radiating elements 21 are excited, the radiating elements 21and the corresponding parasitic elements 22 are magnetically coupled toeach other. In this case, the antennas 20 has two resonant modes havingdifferent resonant frequencies. Thus, compared with the case where theparasitic elements 22 are not provided, a wider bandwidth of each of theantennas 20 can be achieved. In addition, the plurality of antennas 20form an array antenna, and by controlling the arrangement of theradiating elements 21 of the antennas 20 or the amplitude and the phaseof the exciting high-frequency signal, a desired radiation pattern(directivity) can be obtained.

The configuration of the control circuit 30 will now be described. FIG.4 is a block diagram illustrating a configuration example of the antennamodule according to the first embodiment. FIG. 5 is a graphschematically illustrating a relationship between an output signal andan electrically conductive condition of an antenna. Note that, in FIG. 4, a case will be described in which the antenna module 1 includes nnumber of antennas 20. In other words, as illustrated in FIG. 4 , theantenna module 1 includes a first antenna (ANT1) 20-1, a second antenna(ANT2) 20-2, . . . , an n-lth antenna (ANTn−1) 20-(n−1), and an nthantenna (ANTn) 20-n.

As illustrated in FIG. 4 , the control circuit 30 includes the signalprocessing circuit 50 and an antenna inspection circuit 60. The signalprocessing circuit 50 is connected to the antennas 20 via the first feedlines 33 and the second feed lines 34. The signal processing circuit 50contributes to transmission and reception of signals via the antennas20. The antenna inspection circuit 60 is a circuit used for checking theelectrical conductivity of each of the electrical conduction pathsincluding the first feed lines 33, the radiating elements 21 of theantennas 20 (see FIG. 2 ), and the second feed lines 34. The controlcircuit 30 can perform switching between a communication mode and aninspection mode. In the communication mode, the control circuit 30performs transmission and reception of signals via the antennas 20 bythe operation of the signal processing circuit 50 in accordance withcontrol signals from the outside. In the inspection mode, the controlcircuit 30 checks the electrical conductivity of each of the antennas 20by the operation of the antenna inspection circuit 60.

The antenna inspection circuit 60 is electrically connected to the firstfeed lines 33 and the second feed lines 34 via first connection wiringlines L1 and L2. Second connection wiring lines L11 and L12 areconnected to the first connection wiring lines L1 and L2 such that eachof the second connection wiring lines L11 branches off from one of thefirst connection wiring lines L1 and that each of the second connectionwiring lines L12 branches off from one of the first connection wiringlines L2. The signal processing circuit 50 is electrically connected tothe first feed lines 33 and the second feed lines 34 via the secondconnection wiring lines L11 and L12. In other words, each of theantennas 20 is electrically connected to the signal processing circuit50 and the antenna inspection circuit 60.

The signal processing circuit 50 includes a transmission circuit 51 anda reception circuit 52. At the time of transmission, a baseband module 2supplies a baseband signal Va to the transmission circuit 51. Thetransmission circuit 51 modulates the baseband signal Va into ahigh-frequency signal (e.g., 60 GHz). Then, the transmission circuit 51supplies the high-frequency signal to each of the antennas 20 via thefirst feed lines 33 and the second feed lines 34. At the time ofreception, a high-frequency signal from each of the antennas 20 issupplied to the reception circuit 52. The reception circuit 52demodulates the received high-frequency signal into a baseband signal Vband supplies the baseband signal Vb to the baseband module 2. Note thatthe reception circuit 52 may output an intermediate-frequency signalhaving a frequency higher than that of the baseband signal Vb.

An external inspection device 4 that is connected to the control circuit30 is, for example, a tester, a data logger, a personal computer, or thelike. The inspection device 4 includes a control unit 41, a storage unit42, and an input unit 43. The control unit 41 is, for example, anarithmetic processing unit including a central processing unit (CPU).The storage unit 42 stores a software program used for controlling anelectrical conductivity check and various information items such asresults of electrical conductivity checks performed on each of theantennas 20. The storage unit 42 is, for example, a circuit thatfunctions as a non-volatile storage device, such as a flash memory. Theinput unit 43 is, for example, an input device such as a keyboard or atouch panel. An operator inputs information related to an electricalconductivity check by using the input unit 43. In the presentembodiment, the antenna module 1 includes the antenna inspection circuit60. Thus, the configuration of the external inspection device 4 can besimplified. In addition, even if there is a different number of antennas20, electrical conductivity checks can be performed by thegeneral-purpose inspection device 4.

The antenna inspection circuit 60 includes an inspection control circuit61, a power supply terminal 62, a storage circuit 63, a plurality ofdetection circuits 65-1, 65-2, . . . , 65-(n−1), and 65-n, and adetermination circuit 66. Note that, in the following description, whenit is not necessary to distinguish the detection circuits 65-1, 65-2, .. . , 65-(n−1), and 65-n, they will be referred to as the detectioncircuits 65.

The inspection control circuit 61 is a control circuit that controls theoperations of the power supply terminal 62, the storage circuit 63, theplurality of detection circuits 65, and the determination circuit 66.The inspection control circuit 61 controls each electrical conductivitycheck on the basis of a control signal Vc and an inspection start signalVst from the inspection device 4. In addition, the inspection controlcircuit 61 outputs a control signal Vd to the signal processing circuit50 on the basis of the control signal Vc. The signal processing circuit50 stops its operation on the basis of the control signal Vd and stopspower supply to the antennas 20 and input/output of signals when anelectrical conductivity check is performed.

The power supply terminal 62 supplies an input signal Vin for electricalconductivity check to the antennas 20 via the detection circuits 65.

The detection circuits 65-1, 65-2, . . . , 65-(n−1), and 65-n areelectrically connected to the first antenna 20-1, the second antenna20-2, . . . , the n-lth antenna 20-(n−1), and the nth antenna 20-n,respectively, via the first connection wiring lines L1 and L2. Thedetection circuits 65 are circuits that detect output signals Vout fromthe first feed lines 33, the antennas 20, and the second feed lines 34.Each of the detection circuits 65 detects, as the output signal Vout,the inter-terminal voltage between one of the connection terminals 31 towhich one of the first feed lines 33 is connected and one of theconnection terminals 31 to which one of the second feed lines 34 isconnected. Each of the detection circuits 65 outputs the output signalVout to the determination circuit 66. Note that the detection circuits65 are not limited to have the above configuration and may be configuredto detect the current that flows through the first feed lines 33, theantennas 20, and the second feed lines 34.

The determination circuit 66 is a circuit that determines, on the basisof the output signals Vout, the electrical continuity between the firstfeed lines 33, the radiating elements 21 of the antennas 20, and thesecond feed lines 34. The determination circuit 66 is, for example, acircuit that includes a comparator. The determination circuit 66supplies an inspection signal Adet as a digital signal to the storagecircuit 63 for each of the antennas 20, the inspection signal Adetcorresponding to the electrically conductive condition of the antenna20. The determination circuit 66 outputs “1” as the inspection signalAdet when the electrical conductivity of one of the antennas 20 isfavorable and outputs “0” as the inspection signal Adet when theelectrical conductivity of one of the antennas 20 is poor.

FIG. 5 illustrates an example of a determination method used by thedetermination circuit 66. The determination circuit 66 compares theoutput signal Vout and a reference signals Vref1 and Vref2. Thereference signals Vref1 and Vref2 are each a voltage signal based on areference value stored in the storage unit 42 of the inspection device4.

When the output signal Vout is equal to or greater than the referencesignal Vref1 and equal to or less than the reference signal Vref2, thedetermination circuit 66 determines that the electrical conductivity ofthe closed loop that is formed of one of the first feed lines 33, theradiating element 21 of a corresponding one of the antennas 20, and acorresponding one of the second feed lines 34 is favorable (OK). In thiscase, the determination circuit 66 outputs “1” as the inspection signalAdet. In contrast, when the output signal Vout is less than thereference signal Vref1, the determination circuit 66 determines that aportion of the closed loop formed of the first feed line 33, theradiating element 21 of the antenna 20, and the second feed lines 34 isshort-circuited (SHORT). When the output signal Vout is greater than thereference signal Vref2, the determination circuit 66 determines that aportion of the closed loop formed of the first feed line 33, theradiating element 21 of the antenna 20, and the second feed lines 34 isbroken (OPEN). When the determination circuit 66 determines ashort-circuit (SHORT) or a breakage (OPEN), the determination circuit 66outputs “0” as the inspection signal Adet.

The storage circuit 63 is a circuit that stores the inspection signalsAdet for each of the antennas 20. When an electrical conductivity checkis completed, the inspection control circuit 61 outputs the inspectionsignals Adet to the inspection device 4. As a result, the electricalconductivity of each of the antennas 20 can be checked. Note that theconfiguration of the antenna inspection circuit 60 illustrated in FIG. 4is merely an example and may be suitably changed. For example, somefunctions of the antenna inspection circuit 60 such as the storagecircuit 63 may be included in the external inspection device 4.

As described above, the antenna module 1 according to the presentembodiment can check the electrical conductivity of each of theradiating elements 21 disposed in or on an inner layer of the basemember 10 by using the first feed lines 33 and the second feed lines 34,which are used in transmission and reception of signals via the antennas20. If terminals, wiring lines, or the like that are used for electricalconductivity checks are provided separately from the first feed lines 33and the second feed lines 34, there is a possibility that theperformances of the antennas 20 may change in transmission and receptionof millimeter waves in a frequency band of 60 GHz. In the presentembodiment, it is not necessary to provide terminals, wiring lines, orthe like that are used for electrical conductivity checks, and thus,changes in the performances of the antennas 20 can be suppressed.

A method for checking the electrical conductivity of the antenna module1 will now be described with reference to FIG. 4 to FIG. 6 . FIG. 6 is aflowchart illustrating a method for checking the electrical conductivityof the antenna module according to the first embodiment. As illustratedin FIG. 6 , the control circuit 30 determines whether the inspectionstart signal Vst is input (step ST1). When the inspection start signalVst is not input (No in step ST1), the control circuit 30 determineswhether a communication control signal is input (step ST8). Thecommunication control signal is a signal for controlling functions oftransmitting and receiving signals via an antenna and is supplied from,for example, a control board (not illustrated). When the communicationcontrol signal is input (Yes in step ST8), the control circuit 30switches to the communication mode (step ST9). As a result, the signalprocessing circuit 50 performs transmission and reception of signals viathe antennas 20. When the communication control signal is not input (Noin step ST8), the control circuit 30 does not switch to either thecommunication mode or the inspection mode, and the process returns tostep ST1.

When the inspection start signal Vst is input (Yes in step ST1), thecontrol circuit 30 switches to the inspection mode (step ST2). Theinspection control circuit 61 uses the inspection start signal Vst as atrigger and causes the power supply terminal 62, the storage circuit 63,the plurality of detection circuits 65, and the determination circuit 66to operate. First, the inspection control circuit 61 performs anelectrical conductivity check on the first antenna 20-1 (step ST3). Bythe operations of the power supply terminal 62, the detection circuit65-1, and the determination circuit 66, the inspection signal Adetcorresponding to the electrically conductive condition of the firstantenna 20-1 is stored in the storage circuit 63. When the electricalconductivity check performed on the first antenna 20-1 is complete, theinspection control circuit 61 performs an electrical conductivity checkon the second antenna 20-2 (step ST4). Similarly, the inspection controlcircuit 61 sequentially performs electrical conductivity checks on theother antennas 20, performs an electrical conductivity check on the(n−1)th antenna 20-(n−1) (step ST5), and performs an electricalconductivity check on the nth antenna 20-n (step ST6).

As described above, the inspection control circuit 61 sequentiallychecks the electrical conductivity of each of the plurality of antennas20. Then, the inspection signals Adet corresponding to all the antennas20 that have been checked are stored in the storage circuit 63. When theelectrical conductivity checks on all the antennas 20 are complete, theinspection control circuit 61 outputs the inspection results to theinspection device 4 (step ST7). In the present embodiment, theinspection results that are supplied to the inspection device 4 are theinspection signals Adet corresponding to all the antennas 20. As aresult, among the plurality of antennas 20, the antenna 20 in which anelectrical conduction abnormality has occurred can be determined.

The electrical conductivity checking method that is illustrated in FIG.6 is merely an example and may be suitably changed. FIG. 7 is aflowchart illustrating another example of the method for checking theelectrical conductivity of the antenna module according to the firstembodiment. As illustrated in FIG. 7 , the steps of performing switchingbetween the communication mode and the inspection mode (steps ST11,ST12, ST17, and ST18) are similar to those in the method that isillustrated in FIG. 6 as an example.

First, the inspection control circuit 61 uses the inspection startsignal Vst as a trigger and performs an electrical conductivity check onthe first antenna 20-1 (step ST13-1). The determination circuit 66determines whether the electrical conductivity of the first antenna 20-1is favorable (step ST13-2). When the electrical conductivity of thefirst antenna 20-1 is poor (short-circuit or breakage) (No in stepST13-2), the inspection control circuit 61 terminates the electricalconductivity check on the basis of the inspection signal Adet from thedetermination circuit 66 and outputs the inspection result to theinspection device 4 (step ST16). The inspection result in this caseindicates that an electrical conduction failure has occurred in theantenna module 1.

When the electrical conductivity of the first antenna 20-1 is favorable(Yes in step ST13-2), the inspection control circuit 61 performs anelectrical conductivity check on the second antenna 20-2 (step ST14-1).

The determination circuit 66 determines whether the electricalconductivity of the second antenna 20-2 is favorable (step ST14-2). Whenthe electrical conductivity of the second antenna 20-2 is poor(short-circuit or breakage) (No in step ST14-2), the inspection controlcircuit 61 terminates the electrical conductivity check and outputs theinspection result to the inspection device 4 (step ST16). When theelectrical conductivity of the second antenna 20-2 is favorable (Yes instep ST14-2), electrical conductivity checks are sequentially performedon the other antennas 20 in a similar manner to the above.

The inspection control circuit 61 performs an electrical conductivitycheck on the nth antenna 20-n (step ST15-1). The determination circuit66 determines whether the electrical conductivity of the nth antenna20-n is favorable (step ST15-2). When the electrical conductivity of thenth antenna 20-n is poor (short-circuit or breakage) (No in stepST15-2), the inspection control circuit 61 terminates the electricalconductivity check and outputs the inspection result to the inspectiondevice 4 (step ST16). When the electrical conductivity of the nthantenna 20-n is favorable (Yes in step ST15-2), the inspection controlcircuit 61 terminates the electrical conductivity check and outputs theinspection results indicating that all the antennas 20 have favorableelectrical conductivity to the inspection device 4 (step ST16).

As described above, in the other example of the embodiment of thepresent application, when it is detected that an electrical conductionfailure has occurred in any one of the plurality of antennas 20, it isdetermined that an electrical conduction failure has occurred in theantenna module 1, and the electrical conductivity check is terminated.Since the electrical conductivity check is terminated when any one ofthe antennas 20 is determined to be a faulty antenna, the electricalconductivity check can be performed in a shorter time compared with themethod in which a determination is made after all the antennas 20 havebeen checked. In addition, it is not necessary to hold the inspectionsignals Adet of the individual antennas 20, the circuit size of thestorage circuit 63 can be reduced.

(Modification)

FIG. 8 is a block diagram illustrating a configuration example of anantenna module according to a modification of the first embodiment. Inan antenna module 1A of the present embodiment, the antenna inspectioncircuit 60 further includes a connection switching circuit 64. Inaddition, only one detection circuit 65 is provided. The connectionswitching circuit 64 is a switch circuit that switches the connectionbetween the detection circuit 65, and each of the antennas 20 inaccordance with control signals from the inspection control circuit 61.

In the inspection mode, the inspection control circuit 61 connects thedetection circuit 65 and the first antenna 20-1 to each other by theoperation of the connection switching circuit 64 and performs anelectrical conductivity check on the first antenna 20-1. Then, theinspection control circuit 61 connects the detection circuit 65 and thesecond antenna 20-2 to each other by the operation of the connectionswitching circuit 64 and performs an electrical conductivity check onthe second antenna 20-2. In this manner, the connection switchingcircuit 64 sequentially connects the detection circuit 65 and each ofthe antennas 20 in a time division manner. As a result, the antennamodule 1A can perform electrical conductivity checks on all the antennas20 in a similar manner to the electrical conductivity checking methodthat is illustrated in FIG. 6 .

In the present modification, since the connection switching circuit 64is provided, it is not necessary to provide the detection circuit 65 foreach of the antennas 20. Thus, in the case where the number of theantennas 20 is large, the circuit size of the antenna inspection circuit60 can be reduced.

As described above, each of the antenna modules 1 and 1A of the presentembodiment includes the base member 10, the antennas 20 including theradiating elements 21 provided on the inner layer of the base member 10,the first feed lines 33, the second feed lines 34, and the controlcircuit 30, the first feed lines 33 and the second feed lines 34 beingconnected to the radiating elements 21, and the control circuit 30 beingconnected to the radiating elements 21 via the first feed lines 33 andthe second feed lines 34. The control circuit 30 includes the signalprocessing circuit 50, which is connected to the antennas 20 via thefirst feed lines 33 or the second feed lines 34, and the antennainspection circuit 60 that checks the electrical conductivity of each ofthe electrical conduction paths including the first feed lines 33 theradiating elements 21, and the second feed lines 34.

According to the above-described configuration, the electricalconductivity of each of the radiating elements 21 disposed on the innerlayer of the base member 10 can be checked by using the first feed lines33 and the second feed lines 34, which are used in transmission andreception of signals via the antennas 20. In addition, since it is notnecessary to provide terminals, wiring lines, or the like that are usedfor electrical conductivity checks, changes in the signaltransmission/reception performances via the antennas 20 can besuppressed. Furthermore, since the control circuit 30 includes theantenna inspection circuit 60 that checks the electrical conductivity ofeach of the antennas 20, electrical conductivity checks can be easilyperformed without necessarily bringing a probe into contact with each ofthe antennas 20.

In each of the antenna modules 1 and 1A of the present embodiment, thecontrol circuit 30 performs switching between the communication mode inwhich transmission and reception of signals via the antennas 20 isperformed by the operation of the signal processing circuit 50 and theinspection mode in which the electrical conductivity of each of theelectrical conduction paths is checked by the operation of the antennainspection circuit 60. According to this configuration, the first feedlines 33 and the second feed lines 34 can be commonly used in thecommunication mode and the inspection mode. In addition, the operationsin the inspection mode are performed during a period different from theperiod when the operations in the communication mode are performed, andthus, changes in the signal transmission/reception performances via theantennas 20 can be suppressed.

In each of the antenna modules 1 and 1A of the present embodiment, theantenna inspection circuit 60 includes the detection circuits 65 thatdetects the output signals Vout from the first feed lines 33, theradiating elements 21, and the second feed lines 34 and thedetermination circuit 66 that determines the electrical conductivity ofeach of the electrical conduction paths on the basis of the outputsignals Vout. According to this configuration, it can be checked whetherthe electrical conductivity is favorable or abnormal from determinationresults obtained by the determination circuit 66. In addition, since theantenna inspection circuit 60 includes the detection circuits 65 and thedetermination circuit 66, the configuration of the inspection device 4that is used for electrical conductivity checks and that is connected tothe antenna modules 1 or 1A can be simplified.

In each of the antenna modules 1 and 1A of the present embodiment, theplurality of antennas 20 are arranged on and in the base member 10, theantenna inspection circuit 60 sequentially checks the electricalconductivity of the electrical conduction paths for the plurality ofantennas 20 and outputs inspection results of all the antennas 20 thathave been checked. According to this configuration, among the pluralityof antennas 20, the antenna 20 in which an electrical conductionabnormality has occurred can be easily determined.

In each of the antenna modules 1 and 1A of the present embodiment, theplurality of antennas 20 are arranged on and in the base member 10, andthe antenna inspection circuit 60 sequentially checks the electricalconductivity of the electrical conduction paths for the plurality ofantennas 20 and terminates the electrical conductivity check when anelectrical conduction abnormality is detected in any one of the antennas20. According to this configuration, it is not necessary to check allthe antennas 20, and the electrical conductivity check can be performedin a short time.

In each of the antenna modules 1 and 1A of the present embodiment, thebase member 10 has the first surface 10 a and the second surface 10 bthat is opposite to the first surface 10 a. The antennas 20 furtherinclude the parasitic elements 22 that are disposed on the first surface10 a so as to face the corresponding radiating elements 21, and thecontrol circuit 30 is mounted on the second surface 10 b of the basemember 10. According to this configuration, a wider bandwidth of each ofthe antennas 20 can be achieved.

In the method for inspecting each of the antenna modules 1 and 1A of thepresent embodiment, the control circuit 30 switches to the inspectionmode in which the electrical conductivity of each of the electricalconduction paths is checked, and the antenna inspection circuit 60sequentially checks the electrical continuity between the first feedlines 33, the radiating elements 21, and the second feed lines 34 forthe plurality of antennas 20.

Note that the configurations of the antenna modules 1 and 1A can besuitably changed. For example, in FIG. 1 to FIG. 3 , the configurationsof the antennas 20, the first feed lines 33, the second feed lines 34,and the control circuit 30 are schematically illustrated for ease ofunderstanding, and the configuration of the antenna module 1 is notlimited to the configuration illustrated in FIG. 1 to FIG. 3 . Forexample, the arrangement of the antennas 20 and the number of theantennas 20 can be suitably changed. The present disclosure is notlimited to the case where the plurality of antennas 20 are provided, andone antenna 20 may be provided. An antenna different from the antennas20 or a circuit element may be provided in or on the base member 10. Aground layer or the like may be included in the base member 10 as aninner layer of the base member 10. The antennas 20 may not include theparasitic elements 22 and may include only the radiating elements 21.

Second Embodiment

FIG. 9 is a plan view illustrating radiating elements of an antennamodule according to a second embodiment. FIG. 10 is a block diagramillustrating a configuration example of the antenna module according tothe second embodiment. As illustrated in FIG. 9 , in an antenna module1B of the present embodiment, the antennas 20 have third ports 25 andfourth ports 26 in addition to the first ports 23 and the second ports24. Each of the third ports 25 is provided on the side opposite to theside on which one of the second ports 24 is provided with the center ofone of the antennas 20 interposed therebetween. Each of the fourth ports26 is provided on the side opposite to the side on which one of thefirst ports 23 is provided with the center of one of the antennas 20interposed therebetween.

As illustrated in FIG. 10 , each of the antennas 20 is connected to oneof the first feed lines 33, one of the second feed lines 34, one ofthird feed lines 35, and one of fourth feed lines 36. The first feedlines 33 are connected to the first ports 23 illustrated in FIG. 9 .Similarly, the second feed lines 34 are connected to the second ports24. The third feed lines 35 are connected to the third ports 25. Thefourth feed lines 36 are connected to the fourth ports 26.

The first feed lines 33, the second feed lines 34, the third feed lines35, and the fourth feed lines 36 are electrically connected to theantenna inspection circuit 60 via the first connection wiring lines L1,the first connection wiring lines L2, first connection wiring lines L3,and first connection wiring lines L4, respectively. The first feed lines33, the second feed lines 34, the third feed lines 35, and the fourthfeed lines 36 are electrically connected to the signal processingcircuit 50 the second connection wiring lines L11, the second connectionwiring lines L12, second connection wiring lines L13, and secondconnection wiring lines L14, respectively.

In the communication mode, the signal processing circuit 50 can supplyhigh-frequency signals to the antennas 20 via the first feed lines 33,the second feed lines 34, the third feed lines 35, and the fourth feedlines 36. Even if breakage of any one of the first feed lines 33, thesecond feed lines 34, the third feed lines 35, and the fourth feed lines36 occurs, transmission and reception of signals via the antennas 20 canbe performed.

Also in the present embodiment, electrical conductivity checks can beperformed by using the first feed lines 33, the second feed lines 34,the third feed lines 35, and the fourth feed lines 36. Note that,although FIG. 10 illustrates the configuration in which the connectionbetween the detection circuits 65 and each of the antennas 20 isswitched by the connection switching circuit 64, the present disclosureis not limited to this configuration. Also in the present embodiment, aconfiguration can be employed in which a plurality of detection circuits65 are provided so as to correspond in one-to-one to the antennas 20 asin the configuration illustrated in FIG. 4 .

FIG. 11 is a flowchart illustrating a method for checking the electricalconductivity of the antenna module according to the second embodiment.As illustrated in FIG. 11 , the steps of performing switching betweenthe communication mode and the inspection mode (steps ST21, ST22, ST27,and ST28) are similar to those in the method that is illustrated in FIG.6 as an example.

First, the inspection control circuit 61 uses the inspection startsignal Vst as a trigger and performs an electrical conductivity check onthe first antenna 20-1 (step ST23). The inspection control circuit 61checks the electrical continuity between the first feed line 33 and thesecond feed line 34 of the first antenna 20-1 (step ST23-1). Morespecifically, the detection circuits 65 detects the output signals Voutthat are output by the first feed line 33, the radiating element 21 ofthe first antenna 20-1, and the second feed line 34. The determinationcircuit 66 determines the electrical continuity between the first feedline 33, the radiating element 21 of the first antenna 20-1, and thesecond feed line 34 on the basis of the output signals Vout. As aresult, the electrical continuity between the first feed line 33 and thesecond feed line 34 is checked.

Similarly, the inspection control circuit 61 checks the electricalcontinuity between the third feed line 35 and the fourth feed line 36 ofthe first antenna 20-1 (step ST23-2). When the electrical continuitybetween the first feed line 33 and the second feed line 34 is favorable,and the electrical continuity between the third feed line 35 and thefourth feed line 36 is favorable, the determination circuit 66determines that the electrical conductivity of the first antenna 20-1 isfavorable. When at least one of the electrical continuity between thefirst feed line 33 and the second feed line 34 and the electricalcontinuity between the third feed line 35 and the fourth feed line 36 ispoor, it is determined that an electrical conduction failure hasoccurred in the first antenna 20-1.

Similarly, the inspection control circuit 61 sequentially performselectrical conductivity checks on the second antenna 20-2 to the nthantenna 20-n (step ST24, ST24-1, ST24-2, ST25, ST25-1, and ST25-2). Whenthe electrical conductivity checks on all the antennas 20 are complete,the inspection control circuit 61 outputs the inspection results to theinspection device 4 (step ST26). In the present embodiment, theinspection results that are supplied to the inspection device 4 may bethe inspection signals Adet corresponding to all the antennas 20 or maybe the inspection signals Adet, each of which corresponds to a pair ofthe feed lines. As a result, among the plurality of antennas 20, theantenna 20 in which an electrical conduction abnormality has occurredcan be easily determined.

Note that the present disclosure is not limited to the exampleillustrated in FIG. 11 , and when it is detected that an electricalconduction failure has occurred in any one of the plurality of antennas20, it may be determined that an electrical conduction failure hasoccurred in the antenna module 1, and the electrical conductivity checkmay be terminated. In addition, in an electrical conductivity check thatis performed on one of the antennas 20, the two feed lines to beselected may be suitably changed. For example, the electrical continuitybetween the first feed lines 33 and the third feed lines 35 may bechecked, and the electrical continuity between the second feed line 34and the fourth feed line 36 may be checked.

Third Embodiment

FIG. 12 is a sectional view illustrating an antenna module according toa third embodiment. Unlike the above-described embodiments, aconfiguration in which the parasitic elements 22 are not provided willbe described in the third embodiment. As illustrated in FIG. 12 , theantennas 20 include the radiating elements 21. The radiating elements 21are disposed on the first surface 10 a (the front surface) of the basemember 10 and are exposed at the base member 10. In an antenna module 1Cthat has such a configuration, the configuration of each of the antennas20 can be more simplified than that in each of the first and secondembodiments.

Note that the configuration according to the third embodiment can alsobe applied to the antenna modules 1, 1A, and 1B of the first and secondembodiments.

FIG. 13 is a sectional view illustrating an antenna module according toa first modification of the third embodiment. Unlike the above-describedthird embodiment, a configuration in which a protective layer 12 isprovided will be described in the first modification of the thirdembodiment. As illustrated in FIG. 13 , the protective layer 12 isprovided on the first surface 10 a (the front surface) of the basemember 10 so as to cover the radiating elements 21. The protective layer12 is made of, for example, a resin material that is used as a solderresist. In an antenna module 1D that has such a configuration, theantennas 20 are protected by the protective layer 12, so that thepossibility that the antennas 20 will become damaged can be furtherreduced than in the third embodiment.

Note that the configuration according to the first modification of thethird embodiment in which the protective layer 12 is provided can alsobe applied to the antenna modules 1, 1A, and 1B of the first, second,and third embodiments.

FIG. 14 is a sectional view illustrating an antenna module according toa second modification of the third embodiment. Unlike the thirdembodiment and the first modification, which have been described above,a configuration in which a shield member 13 is provided will bedescribed in the second modification of the third embodiment. Asillustrated in FIG. 14 , the shield member 13 is provided on the secondsurface 10 b of the base member 10 so as to cover the control circuit30. The shield member 13 is made of a metal material having electricalconductivity and is connected to a ground potential of the base member10. As a result, the shield member 13 electromagnetically shields thecontrol circuit 30. The shield member 13 includes a flat plate thatfaces the second surface 10 b and a side plate that surrounds thecontrol circuit 30. In an antenna module 1E that has such aconfiguration, the control circuit 30 is protected by the shield member13, and interference between signals radiated by the antennas 20 and thecontrol circuit 30 can be suppressed. Note that, although the interiorof the shield member 13 is hollow, the present disclosure is not limitedto this configuration. For example, the sealing resin 11 may be providedin the interior of the shield member 13.

Note that the configuration according to the second modification of thethird embodiment can also be applied to the antenna modules 1 and 1A to1E of the first to third embodiments and the first and the secondmodifications of the third embodiment.

FIG. 15 is a sectional view illustrating an antenna module according toa third modification of the third embodiment. Unlike the thirdembodiment and the first and second modifications of the thirdembodiment, which have been described above, a configuration in which acircuit board 14 is provided will be described in the third modificationof the third embodiment. As illustrated in FIG. 14 , the circuit board14 has a first surface 14 a and a second surface 14 b that is oppositeto the first surface 14 a. The first surface 14 a of the circuit board14 is positioned so as to face the second surface 10 b of the basemember 10. The circuit board 14 and the base member 10 are electricallyconnected to each other via connection terminals 16. The circuit board14 has a plurality of signal paths 15, and the first feed lines 33 andthe second feed lines 34 of the base member 10 are connected to thesignal paths 15 by the connection terminals 16.

The control circuit 30 is mounted on the second surface 14 b of thecircuit board 14, that is, the surface of the circuit board 14 that isopposite to the surface of the circuit board 14 facing the base member10. As a result, the first feed lines 33 and the second feed lines 34are electrically connected to the control circuit 30 via the pluralityof signal paths 15 of the circuit board 14. The sealing resin 11 isprovided on the second surface 14 b of the circuit board 14 so as tocover the control circuit 30.

The thickness of the circuit board 14 is smaller than the thickness ofthe base member 10. As a result, a wider bandwidth of each of theantennas 20 can be achieved while an increase in the entire thickness ofan antenna module 1F is suppressed. In addition, the arrangement pitchof the connection terminals 31 of the control circuit 30 and thearrangement pitch of the connection terminals 16 of the circuit board 14are different from each other. Thus, the antenna module 1F can improvethe degree of freedom in arranging the connection terminals 31 of thecontrol circuit 30 and the degree of freedom in routing the first feedlines 33 and the second feed lines 34. In other words, even in the caseof changing routing of the first feed lines 33 and the second feed lines34, by changing the connection terminals 16 and the signal paths 15 ofthe circuit board 14, the connection terminals 31 of the control circuit30 do not need to be changed. Alternatively, even in the case ofchanging the arrangement of the connection terminals 31 of the controlcircuit 30, by changing the circuit board 14 in accordance with thecontrol circuit 30, the first feed lines 33 and the second feed lines 34of the base member 10 do not need to be changed.

Note that the configuration according to the third modification of thethird embodiment can also be applied to the antenna modules 1 and 1A to1E of the first to third embodiments and the first to thirdmodifications of the third embodiment.

FIG. 16 is a sectional view illustrating an antenna module according toa fourth modification of the third embodiment. Unlike the thirdembodiment and the first to third modifications of the third embodiment,which have been described above, a configuration in which the controlcircuit 30 and the base member 10 are mounted on the same surface of acircuit board 14A will be described in the fourth modification of thethird embodiment. As illustrated in FIG. 16 , the circuit board 14A hasan area larger than that of the base member 10 when viewed in plan view.The control circuit 30 and the base member 10 are mounted on a firstsurface 14Aa of the circuit board 14A. No circuit or component ismounted on a second surface 14Ab of the circuit board 14A. The firstfeed lines 33 and the second feed lines 34 are electrically connected tothe control circuit 30 via the signal paths 15 of the circuit board 14A.With such a configuration, since the control circuit 30 and the basemember 10 are mounted on the same surface of the circuit board 14A in aprocess of manufacturing an antenna module 1G, the process of mountingthe control circuit 30 and the base member 10 can be easily performed.

Note that the configuration according to the fourth modification of thethird embodiment can also be applied to the antenna modules 1 and 1A to1E of the first to third embodiments and the first to thirdmodifications of the third embodiment.

Fourth Embodiment

FIG. 17 is a block diagram illustrating a configuration example of anantenna module according to a fourth embodiment. Unlike the first tothird embodiments, which have been described above, in the fourthembodiment, a configuration in which the first connection wiring linesL1 and L2 and the second connection wiring lines L11 and L12 areprovided so as to be connectable to ground terminals 68 will bedescribed. As illustrated in FIG. 17 , the control circuit 30 includesthe ground terminals 68 and switches SW. Each of the switches SWperforms, on the basis of a control signal from the inspection controlcircuit 61, a switching operation for connecting and disconnecting oneof the first connection wiring lines L2 and one of the ground terminals68. A first end of each of the switches SW is connected to a portion ofone of the first connection wiring lines L2, the portion being locatedbetween a position where the first connection wiring line L2 and acorresponding one of the second connection wiring lines L12 areconnected to each other and one of the detection circuits 65. A secondend of each of the switches SW is connected to the corresponding groundterminal 68. For example, the ground terminals 68 are electricallyconnected to a ground layer of the base member 10. All the firstconnection wiring lines L2, each of which corresponds to one of theantennas 20, are connectable to the ground terminals 68 via the switchesSW. Note that the first ends of the switches SW may be connected to thefirst connection wiring lines L1.

With such a configuration, for example, the control circuit 30 switcheson the switches SW after the process in the inspection mode that isillustrated in FIG. 6 has been terminated. As a result, the firstconnection wiring lines L1 and L2 and the second connection wiring linesL11 and L12 are electrically connected to the ground terminals 68. Thestatic electricity accumulated in the first connection wiring lines L1and L2 and the second connection wiring lines L11 and L12 during theinspection mode flows to the ground layer via the switches SW and theground terminals 68. As a result, an antenna module 1H suppresses theelectrification of the first connection wiring lines L1 and L2 and thesecond connection wiring lines L11 and L12 and can take measures againstelectrostatic discharge (ESD). In the communication mode, the controlcircuit 30 switches off the switches SW. As a result, the firstconnection wiring lines L1 and L2 and the second connection wiring linesL11 and L12 are disconnected from the ground terminals 68.

FIG. 18 is a block diagram illustrating a configuration example of anantenna module according to a first modification of the fourthembodiment. Unlike the above-described fourth embodiment, in the firstmodification of the fourth embodiment, a configuration will be describedin which the first end of each of the switches SW is connected to aportion of one of the first connection wiring lines L2, the portionbeing located between a position where the first connection wiring lineL2 and a corresponding one of the second connection wiring lines L12 areconnected to each other and one of the connection terminals 31 to whichone of the second feed lines 34 is connected. Even in such aconfiguration, the static electricity accumulated in the firstconnection wiring lines L1 and L2 and the second connection wiring linesL11 and L12 during the inspection mode flows to the ground layer via theswitches SW and the ground terminals 68. As a result, an antenna module1I can take measures against ESD. Note that the first end of each of theswitches SW may be connected to a portion of one of the first connectionwiring lines L1, the portion being located between a position where thefirst connection wiring line L1 and a corresponding one of the secondconnection wiring lines L11 are connected to each other and one of theconnection terminals 31 to which one of the first feed lines 33 isconnected.

FIG. 19 is a block diagram illustrating a configuration example of anantenna module according to a second modification of the fourthembodiment. Unlike the fourth embodiment and the first modification ofthe fourth embodiment, which have been described above, a configurationin which the second connection wiring lines L11 are connected to theground terminals 68 will be described in the second modification of thefourth embodiment. As illustrated in FIG. 19 , the first end of each ofthe switches SW is connected to one of the second connection wiringlines L11, and the second end of each of the switches SW is connected toone of the ground terminals 68. As a result, each of the switches SWperforms a switching operation for connecting and disconnecting one ofthe second connection wiring lines L11 and a corresponding one of theground terminals 68. The static electricity accumulated in the firstconnection wiring lines L1 and L2 and the second connection wiring linesL11 and L12 during the inspection mode flows to the ground layer via theswitches SW and the ground terminals 68. As a result, an antenna module1J can take measures against ESD.

FIG. 20 is a block diagram illustrating a configuration example of anantenna module according to a third modification of the fourthembodiment. Unlike the fourth embodiment and the first and secondmodifications of the fourth embodiment, which have been described above,a configuration in which the second connection wiring lines L11 areconnected to ground layers 67 via inductance elements 100 will bedescribed in the third modification of the fourth embodiment. Asillustrated in FIG. 20 , the second connection wiring lines L11 areconnected to the ground terminals 68. The ground terminals 68 areconnected to the ground layers 67 via the inductance elements 100 thatare provided outside the control circuit 30. As a result, the pluralityof first connection wiring lines L1 and L2 and the plurality of secondconnection wiring lines L11 and L12 are electrically connected to theground terminals 68.

The inductance elements 100 may be included in the base member 10 (seeFIG. 2 ) or may be included in the circuit board 14 (see FIG. 15 ). Theinductance elements 100 may be arranged in the control circuit 30. Thestatic electricity accumulated in the first connection wiring lines L1and L2 and the second connection wiring lines L11 and L12 during theinspection mode flows to the ground layers 67 via the inductanceelements 100. As a result, an antenna module 1K can take measuresagainst ESD. The inductance elements 100, each has a sufficiently highimpedance with respect to signals that are transmitted by the signalprocessing circuit 50 and signals that are received by the antennas 20.Thus, in the communication mode, signals that are output by the signalprocessing circuit 50 and signals that are received by the antennas 20are not supplied to the ground layers 67.

Note that the inductance elements 100 are not limited to being providedoutside the control circuit 30. Similar to the switches SW illustratedin FIG. 19 , the inductance elements 100 may be arranged in the controlcircuit 30.

Note that the configurations according to the fourth embodiment and themodifications of the fourth embodiment can also be applied to theantenna modules 1 and 1A to 1G of the first to third embodiments.

Fifth Embodiment

FIG. 21 is a sectional view illustrating an antenna module according toa fifth embodiment. Unlike the first to fourth embodiments, which havebeen described above, a configuration in which the signal processingcircuit 50 and the antenna inspection circuit 60 are formed of discreteICs will be described in the fifth embodiment. As illustrated in FIG. 21, in an antenna module 1L, the signal processing circuit 50 and theantenna inspection circuit 60 are arranged on the second surface 10 b ofthe base member 10. The first ends of the first feed lines 33 and thefirst ends of the second feed lines 34 are each connected to one of theradiating elements 21, and the second ends of the first feed lines 33and the second ends of the second feed lines 34 are connected to thesignal processing circuit 50 via connection terminal 50 a. First ends offirst connection lines 37 are connected to the first feed lines 33, andsecond ends of the first connection lines 37 are connected to theantenna inspection circuit 60 via connection terminals 60 a. First endsof second connection lines 38 are connected to the second feed lines 34,and second ends of the second connection lines 38 are connected to theantenna inspection circuit 60 via the connection terminals 60 a.

Also in such a configuration, the antenna inspection circuit 60 cancheck the electrical conductivity of each electrical conduction pathincluding the first connection lines 37, the first feed lines 33, theradiating elements 21 of the antennas 20, the second feed lines 34, andthe second connection lines 38. In the present embodiment, since thesignal processing circuit 50 and the antenna inspection circuit 60 areformed of discrete ICs, each circuit configuration can be easilyoptimized.

Note that the configuration according to the fifth embodiment can alsobe applied to the antenna modules 1 and 1A to 1K of the first to fourthembodiments, which have been described above.

REFERENCE SIGNS LIST

-   -   1, 1A to 1L antenna module    -   2 baseband module    -   4 inspection device    -   10 base member    -   10 a first surface    -   10 b second surface    -   11 sealing resin    -   12 protective layer    -   13 shield member    -   14, 14A circuit board    -   15 signal path    -   16 connection terminal    -   20 antenna    -   21 radiating element    -   22 passive element    -   23 first port    -   24 second port    -   25 third port    -   26 fourth port    -   27 via    -   28 pad    -   29 wiring line    -   30 control circuit    -   31 connection terminal    -   33 first feed line    -   34 second feed line    -   35 third feed line    -   36 fourth feed line    -   41 control unit    -   42 storage unit    -   43 input unit    -   50 signal processing circuit    -   51 transmitting circuit    -   52 receiving circuit    -   60 antenna inspection circuit    -   61 inspection control circuit    -   62 power supply terminal    -   63 storage circuit    -   64 connection switching circuit    -   65 detection circuit    -   66 determining circuit

1. An antenna module comprising: a base member; an antenna comprising aradiating element in or on the base member; a first feed line and asecond feed line that are connected to the radiating element; and acontrol circuit that is connected to the radiating element via the firstfeed line and the second feed line, wherein the control circuitcomprises: a signal processing circuit that is connected to the antennavia the first feed line and the second feed line, and an antennainspection circuit configured to check an electrical conductivity of anelectrical conduction path, the electrical conduction path connectingthe first feed line, the radiating element, and the second feed line toeach other, wherein the base member has a first surface and a secondsurface, the second surface being opposite the first surface, whereinthe antenna is on the first surface, and wherein the control circuit ison the second surface of the base member.
 2. The antenna moduleaccording to claim 1, wherein the radiating element is in or on asurface of the base member, and wherein the antenna module furthercomprises a protective layer that is on the surface of the base memberand that covers the radiating element.
 3. The antenna module accordingto claim 1, further comprising: a circuit board having a first surfacethat faces the base member and that is electrically connected to thebase member, wherein the control circuit is on a second surface of thecircuit board, the second surface being opposite the first surface. 4.The antenna module according to claim 1, further comprising: a shieldthat covers the control circuit.
 5. The antenna module according toclaim 1, wherein the signal processing circuit and the antennainspection circuit are discrete integrated circuits.
 6. The antennamodule according to claim 1, wherein the control circuit comprises: aplurality of first connection wiring lines that connect the first feedline and the second feed line to the antenna inspection circuit, aplurality of second connection wiring lines that connect the first feedline and the second feed line to the signal processing circuit, a groundterminal, and a switch configured to selectively connect and disconnectthe first connection wiring lines to the ground terminal.
 7. The antennamodule according to claim 6, wherein a first end of the switch isconnected to the first connection wiring lines between the antennainspection circuit and a position at which the first connection wiringlines are connected to the second connection wiring lines, and a secondend of the switch is connected to the ground terminal.
 8. The antennamodule according to claim 6, wherein a first end of the switch isconnected to the first connection wiring lines between a position atwhich the first connection wiring lines are connected to the secondconnection wiring lines and a connection terminal at which the firstfeed line and the second feed line are connected to the first connectionwiring lines, and a second end of the switch is connected to the groundterminal.
 9. The antenna module according to claim 1, wherein thecontrol circuit comprises: a plurality of first connection wiring linesthat connect the first feed line and the second feed line to the antennainspection circuit, a plurality of second connection wiring lines thatconnect the first feed line and the second feed line to the signalprocessing circuit, a ground terminal, and a switch configured toselectively connect and disconnect the second connection wiring lines tothe ground terminal.
 10. An antenna module comprising: a base member; anantenna comprising a radiating element in or on the base member; a firstfeed line and a second feed line that are connected to the radiatingelement; and a control circuit that is connected to the radiatingelement via the first feed line and the second feed line, wherein thecontrol circuit comprises: a signal processing circuit that is connectedto the antenna via the first feed line and the second feed line, anantenna inspection circuit configured to check an electricalconductivity of an electrical conduction path, the electrical conductionpath connecting the first feed line, the radiating element, and thesecond feed line to each other, and a circuit board that faces the basemember and that is electrically connected to the base member, whereinthe control circuit and the base member are on a same surface of thecircuit board.
 11. The antenna module according to claim 10, wherein theradiating element is in or on a surface of the base member, and whereinthe antenna module further comprises a protective layer that is on thesurface of the base member and that covers the radiating element. 12.The antenna module according to claim 10, further comprising: a circuitboard having a first surface that faces the base member and that iselectrically connected to the base member, wherein the control circuitis on a second surface of the circuit board, the second surface beingopposite the first surface.
 13. The antenna module according to claim10, further comprising: a shield that covers the control circuit. 14.The antenna module according to claim 10, wherein the signal processingcircuit and the antenna inspection circuit are discrete integratedcircuits.
 15. The antenna module according to claim 10, wherein thecontrol circuit comprises: a plurality of first connection wiring linesthat connect the first feed line and the second feed line to the antennainspection circuit, a plurality of second connection wiring lines thatconnect the first feed line and the second feed line to the signalprocessing circuit, a ground terminal, and a switch configured toselectively connect and disconnect the first connection wiring lines tothe ground terminal.
 16. The antenna module according to claim 15,wherein a first end of the switch is connected to the first connectionwiring lines between the antenna inspection circuit and a position atwhich the first connection wiring lines are connected to the secondconnection wiring lines, and a second end of the switch is connected tothe ground terminal.
 17. The antenna module according to claim 15,wherein a first end of the switch is connected to the first connectionwiring lines between a position at which the first connection wiringlines are connected to the second connection wiring lines and aconnection terminal at which the first feed line and the second feedline are connected to the first connection wiring lines, and a secondend of the switch is connected to the ground terminal.
 18. The antennamodule according to claim 10, wherein the control circuit comprises: aplurality of first connection wiring lines that connect the first feedline and the second feed line to the antenna inspection circuit, aplurality of second connection wiring lines that connect the first feedline and the second feed line to the signal processing circuit, a groundterminal, and a switch configured to selectively connect and disconnectthe second connection wiring lines to the ground terminal.
 19. Theantenna module according to claim 10, wherein the control circuitcomprises: a plurality of first connection wiring lines that connect thefirst feed line and the second feed line to the antenna inspectioncircuit, a plurality of second connection wiring lines that connect thefirst feed line and the second feed line to the signal processingcircuit, and a ground terminal connected to the plurality of secondconnection wiring lines, and wherein the ground terminal is connected toa ground layer via an inductance element, the inductance element beingexternal to the control circuit.
 20. The antenna module according toclaim 10, wherein the control circuit comprises: a plurality of firstconnection wiring lines that connect the first feed line and the secondfeed line to the antenna inspection circuit, a plurality of secondconnection wiring lines that connect the first feed line and the secondfeed line to the signal processing circuit, a ground terminal, and aninductance element between the ground terminal and the first connectionwiring lines or the second connection wiring lines.